Macro: COMMON-LISP:ASSERT

package type clhs

Signals an error if the value of TEST-FORM is NIL. Returns NIL.

Optional DATUM and ARGUMENTS can be used to change the signaled error condition and are interpreted as in (APPLY #’ERROR DATUM ARGUMENTS).

Continuing from the signaled error using the CONTINUE restart will allow the user to alter the values of the SETFable locations specified in PLACES and then start over with TEST-FORM.

If TEST-FORM is of the form

(FUNCTION ARG*)

where FUNCTION is a function (but not a special operator like CL:OR, CL:AND, etc.) the results of evaluating the ARGs will be included in the error report if the assertion fails.

Lambda list

(sb-impl::test-form &optional sb-impl::places sb-impl::datum &rest sb-impl::arguments)